The technology that allows for the transmission of sound or other signals by modulation of electromagnetic waves.
A device that can capture (receive) the signal sent over radio waves and render the modulated signal as sound.
An on-board entertainment system in a car, usually including a radio receiver as well as the capability to play audio from recorded media; see also car radio.
A device that can transmit radio signals.
The continuous broadcasting of sound via the Internet in the style of traditional radio.

To use two-way radio to transmit (a message) (to another radio or other radio operator).
To order or assist (to a location), using telecommunications.